1. Field of the Invention
The invention relates to the field of paint applicators and, in particular, to an improved applicator for coating the ends of fasteners protruding from structures.
2. Description of Related Art
In aircraft manufacture most structural elements are joined with fasteners. For corrosion protection, the surfaces of these structural elements are coated with a corrosion inhibiting coating. After assembly, the structural elements must also have the fastener ends (with retaining nuts attached) coated corrosion inhibiting coatings. Spraying on coatings can be used. However, the corrosion inhibiting coatings typically contain chromium compounds and the use of such sprays may cause environmental problems. Brushes can be used, but there use is time consuming. Thus the use of roller applicators becomes one of most effective methods from both environmental and time considerations.
However, prior art roller designs have not been totally effective. A straight roller will not completely cover the fasteners, especially if they are in rows. U.S. Pat. No. 5,410,773 “Pipe Paint Roller” by I. H. Forkner discloses rollers having a U and square shaped notches. These shapes failed to adequately cover in just one pass. In fact, a lot of excess material had to be deposited on the surrounding surfaces before full coverage of the fasteners was accomplished. U.S. Pat. No. 2,929,089 “Paint Applicator For Corners” by W. L. Hall disclosed a roller for corners, with a 90-degree V shaped notch. Tests of this design were also unsuccessful. One of the problems was the shape outer edge collapsed under pressure causing two much of the coating to be deposited on the adjacent surfaces. Thus no prior art applicator design can effectively be used to coat fasteners protruding from a surface.
In addition, it is desirable to eliminate the need for an applicator that does not require that the coating material be imbibed by rolling the coating member in a paint tray. This is a time consuming process. Furthermore, it exposes the user to fumes. Additionally, if the coating material is a two-part system (resin and catalyst) it tends to cure rapidly when exposed to air. Thus once the coating material was poured into the paint tray, it had to be applied immediately.
Coating material applicators having self-contained supply systems are old in the art. They basically comprised a roller assembly connected by a line to a pump/coating reservoir. Coating flow was controlled by turning the pump on and off. Such systems are difficult to use in confined areas. Examples of this type of applicator can be found in US Patent Publication No. US 2003/0021623A1 “Resin Application” by A. R. Harper. The roller handle incorporates a valve to control resin flow to a spreader bar located in proximity to the roller applicator. U.S. Pat. No. 2,743,469 “Roller Type Paint Applicators” by F. D. Ditch discloses a paint roller wherein the rod extending from the handle to the roller axle and the roller axle itself are hollow. A valve mounted in the handle controls paint flow, which is distributed from the axle into the interior of the roller.
There are numerous roller designs wherein the coating material reservoir is contained within the handle. For example, U.S. Pat. No. 3,337,899 “Roller Type Paint Dispenser” by J. M. Rentfrow discloses a device wherein the rod extending from the handle to the roller axle and the roller axle itself are hollow. A reservoir is incorporated into the handle that incorporates a piston biased by a spring that pressurizes the paint therein. A valve is provided for controlling the flow of paint to the roller. However none of these devices disclose a roller applicator suitable for effectively coating the ends of fasteners protruding from a surface.
Thus, it is a primary object of the invention to provide a coating applicator for covering the ends of fasteners protruding from a surface.
It is another primary object of the invention to provide a coating applicator for covering the ends of fasteners protruding from a surface that covers the ends in one pass.
It is a further object of the invention to provide a coating applicator for covering the ends of fasteners protruding from a surface that covers the ends in one pass while applying a minimum amount of coating material to the adjacent surfaces.
It is another object of the invention to provide a coating applicator for covering the ends of fasteners protruding from a surface that covers the ends of fasteners, which has a self contained supply of coating material for providing the coating to the applicator for imbibing thereby.